Related papers: Limits on Q-ball size due to gravity
The smallest classically stable Q-balls are, in fact, generically metastable: in quantum theory they decay into free particles via collective tunneling. We derive general semiclassical method to calculate the rate of this process in the…
MSSM predicts the existence of Q-balls, some of which can be entirely stable. Both stable and unstable Q-balls can play an important role in cosmology. In particular, Affleck-Dine baryogenesis can result in a copious production of stable…
Q-balls are bound-state configurations of complex scalars stabilized by a conserved Noether charge Q. They are solutions to a second-order differential equation that is structurally identical to Euclidean vacuum-decay bounce solutions in…
We find that there exists a soliton-like solution ``I-ball'' in theories of a real scalar field if the scalar potential satisfies appropriate conditions. Although the I-ball does not have any topological or global U(1) charges, its…
We analyze the classical stability of Q-tubes --- charged extended objects in $(3+1)$-dimensional complex scalar field theory. Explicit solutions were found analytically in the piecewise parabolic potential. Our choice of potential allows…
We study Q-ball formation in the expanding universe on 1D, 2D and 3D lattice simulations. We obtain detailed Q-ball charge distributions, and find that the distribution is peaked at Q^{3D}_{peak} \simeq 1.9\times 10^{-2} (|\Phi_{in}|/m)^2,…
Supersymmetric extensions of the standard model predict the existence of non-topological solitons, $Q$-balls. Assuming the standard cosmological history preceded by inflation, $Q$-balls can form in the early universe and can make up the…
This paper is devoted to prove the existence of solitons on lattices. We are interested in solitary waves and solitons whose existence is related to the ratio energy/charge. These solitary waves are called hylomorphic. This class includes…
This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…
In many supersymmetric extensions of the Standard Model the spectrum of states contains stable non-topological solitons, Q-balls. If formed in the Early Universe in sufficient amounts, Q-balls now contribute to cold dark matter. We discuss…
We study q-stars with one or two scalar fields, non-abelian, and fermion-scalar q-stars in 2+1 dimensions in an anti de Sitter or flat spacetime. We fully investigate their properties, such as mass, particle number, radius, numerically, and…
A new class of relativistic stellar structure equations which include the effects of an energy-dependent Newton coupling is presented. Significant modifications in the mass-radius relation for neutron stars are possible only if the running…
The paper, classically, presents an extended Klein-Gordon field system in 3+1 dimensions with a special Q-ball solution. The Q-ball solution is energetically stable, that is, for any arbitrary small deformation above the background of that,…
We construct "Flying Saucer" solitons in supersymmetric N=2 gauge theory which is known to support BPS domain walls with a U(1) gauge field localized on its worldvolume. We demonstrate that this model supports exotic particle-like solitons…
We show the existence of new stable ring-like localized scalar field configurations whose stability is due to a combination of topological and nontopological charges. In that sense these defects may be called semitopological. These rings…
We consider a phase transition induced by the growth of Q-balls in a false vacuum. Such a transition could occur in the early universe in the case of broken supersymmetry with a metastable false vacuum. Small Q-balls with a negative…
We study the existence of cylindrically symmetric electro-magneto-static solitary waves for a system of a nonlinear Klein-Gordon equation coupled with Maxwell's equations in presence of a positive mass and of a nonnegative nonlinear…
We present Jordan-Brans-Dicke and general scalar-tensor gravitational theory in extra dimensions in an asymptotically flat or anti de Sitter spacetime. We consider a special gravitating, boson field configuration, a $q$-star, in 3, 4, 5 and…
We present compact Q-balls in an (Anti-)de Sitter background in D dimensions, obtained with a V-shaped potential of the scalar field. Beyond critical values of the cosmological constant compact Q-shells arise. By including the gravitational…
It is argued that the surface radius of a compact source can not be less than its gravitational radius due to the strong gravitational time dilation effects. The such "topological" difference between the Newtonian and relativistic gravity…